Cooling analysis of castings in green sand molds

The solidification and cooling processes have important influences on the microstructures and the qualities of castings. The released energy from the casting is transported to the sand molds, which results in the vaporization of sand moisture. Therefore, the vaporization interface forms and continually moves outward. The effects of the endothermic or the exothermic reactions resulting from the mold ingredients on the hear transfer rate in the sand mold ale important. To study the cooling process in a casting, the solidification process inside the casting and the heat transfer,node in the sand mold have to be considered. This paper solves the hear transfer governing equations in the casting and in the sand mold, simultaneously. The temperature distributions in the castings and the movements of the vaporization interfaces in the sand molds Ir,ere calculated by a one-dimensional heat transfer model employing the fixed-grid,,method. The influences of the weight fractions of sand moisture and sand ingredients, of the pouting temperatures of the liquid metal, and the casting sizes were discussed.